Improvement in artificial aems



l @geiten Amritav MCOMBER, or sonnNncTADn Nnw YORK.'

l I l Letters Patent No. 60,921, dated Januaryl, 1867.

IMPROVEMENT IN ARTIFICIAL ARMS.

TO ALL WHOM IT MAY CONCERiN:

Be it known that I, ABNER McOMBER, of Schenectady, in the county ofSchenectady, and State of New York, have invented an improved ArtificialArm; and'I do hereby declare that the following is a full, clear, andexact description thereof, reference being had to the accompanyingdrawings, making-a part of this specication, in which-- 4 Figure 1 is aperspective view of the improved artificial arm complete.

Figure 2, shows the upper portion o'f the arm with the hand removed.

Figure 3 is a 'perspective view of the hand. p

Figure 4 is a sectional view showingv the spring thumb and latch, andthe mode of connecting the hand to the artificial stump. Figure 5 is asectional view of the end of the stump,showing the mode of attaching awriting instrument thereto.

Similar letters of reference-indicate corresponding parts in the'severalfigures'.

The main object of this Vinvention is to soconstructan artificial armthat the hand,. or the lower section of the arm, or both, may be readilydetachedtand a writing instrument applied-to l.the stump for the purpose4of affording the wearer a better control of such writing instrumentthan he would have if it was secured to the 'ha-nd, as will be'hereinafter described. Another object` of my invention is to provide aspring thumb of an artificial hand with a spring latch and releasingpin, in such mrnner that the wearer of such Ahand can more convenientlyapply a, fork, a knife, or other article vbetween the thumb and dngersand remove the same there-` from, than can be done with artificial handshitherto constructed, as will be ,hereinafter described.-

To enable others skilled in the art to understand my invention, I willdescribe its construction and operation.

The articial arm which I have represented in the'accompanying drawingsis designed' for a lperson having a stump which is amputated below theelbow, but the invention for holding a writing instrument is applicableto stumps amputated above the elbow, as will be hereinafter shown.

The arm shown in the drawings consists of three sections: Thehand A, thelower arm section B, and the sleeve or strap C. The hand' section, A,terminates at t'he wrist, and has an ellipitical plate, a, secured to itby screws or otherwise, from which project two tongues, b, having eyesthrough them for receiving `a pin, c, by which the hand is secured tothe-stump or section, B. These tongues are arranged diametricallyopposite each other, and 'enter slots, b t', which are made through theelliptical plate, d, whichis secured to the wrist of the section B, asshown in iigs. 2 and 4l The plate a also has two oblong slots, e e, madethroughl it which are diametrically opposite eachother across thelongestpart oi' the plate, for receiving 'springclasps gg', that areapplied to the plated, as shown in ligs.'2 and 5. 'The clasp, g, is madein the form of an open link, as shown in fig. 6, and inserted into anoblong slot in plate eZ, and prevented from being'drawn out ofplaceby'the pin, z'. The lower clasphg, is formed onua long shank, asshown in iig. v7, which enters a slot in plate d, and is secured inplace by means 'of a set-screw, j, as shown in iig. 5. The set-screw jadmits of the clasping portion g being adjusted and set at dii'crentdistances fromithc plate d, according to the angle at which it isdesired to secure the writing instrument to the section 13.5 Theopenends orjaws of the clasp y spring outwards, and are made to claspand hold apen or pencil handle by pressing this clasp inward ;'the lowerclasp g clasps the pen or pencil handle by its elastic action. To usethe devices for holding the 'writing instrument it is onlynecessary'towithdraw the pin e,whicl1 passes through the eyes of the tongues b b,and remove the handsection A. I do not confine this part ot' myinvention to the lower arm `section VB, as it may be appliedsubstantially in the same manner to upper` arm sections, where a personhas had his 'arm removed above the elbow. Nor do I confine my inventionto the precise devices hereiu'described for securing a writinginstrument` to the stump of an artificial arm, as other forms of claspsor holders may be adopted which will answer the purpose. I prefer toemploy self-holding clasps, as they will be found more*convenient thanother forms. 1 Thesecondl part of my invention consists in 'theemployment of a spring thumb, l), 'which Ais `pivoted at k to the handA, and acted upon by an India-rubber spring, l, or any other suitablespring whichwill keep it closed, as indicated in black lines, iig-4.lhe'object of this spring Zis to press or draw the cushion of the thumbdown forcibly upona fork or a knife, and assist in holding suchinstrument between it andthe-fingers. A longspring, m, is -secured atone end'to the. interior of the thumb D,ip'arried back over atransverse'pin, ,oiiJ-the-hand,v and passed under a transverse pin, p.This spring m has a latch, m', formed on it near its rear end, `whichwill catch in front of pin p, when the thumb is opened or lifted up,andhold the thumb in this'position, as indicated in red lines, fig. 4. Apin, s, is`inserted loosely through the ball of the thumb, so as totouch the spring m near lits latch, Iby vmeans of which the latch' m canbe released from its pin p, and the thumballowed to close upon theinstrument Whichis applied to the hand. The object of applying aspringlatch to a spring thumb is -to allow the person wearing an articial handto introduceanything between thethnmb and fingers of such hand withouttheinconvenience of having to hold open the thumb at; the same time. Thespring latch will hold the thumbopen, and allow of the adjustment of a`knife, a fork, or any other thing 'between the thumb andfingersl in theproper position, afterV which the pin s is pressed upon, and the thumballowed to grasp and hold such thing.'- Ing. 1,'1 have shown at t ascrew socket for receiving a male screw formed on the end of a knifeorlforlg, and 'assisting in securingl such linstrument to the hand A.The thumb l) is held vopen by the latch m while such' instrument `isscrewed into the socket t.

I do not wish to bc understood as laying claim to a springtthumb, asartificial hands'have been constructed.

with spring thumbs before my invention.

Having described my invention, what I claim as new, and desireto secureby Letters Patent, is-' 1. The-permanently attached clasps g g', on thestump section of the arm, in combination with the slotted plate a e e',of the opposite section, substantially as andpfor the purposeset-.,forth, y

2. `The application toa spring thumb of an artificial hand, of a latch,or its' equivalent, for holding said thumb open when desired, and meansfor releasing the thumb from the latch, substantially as described.

ABNER Mooi/nana.l i

Witnesses:

HARMoN SEYMOUR, J OHN @GREENE

